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1.
在pH=1.30的H2SO4和3,4-二羟基苯甲醛(DHB)底液中,采用差分脉冲极谱法,测得无机锗的脉冲极谱波.其峰电位为Ep=-0.53V.Ge(Ⅳ)浓度在1.03×10-3-1.04×10-4mol·L-1范围内与峰电流呈线性关系,样品中总锗和无机锗的回收率分别是95.72%和96.43%.  相似文献   

2.
差分脉冲极谱法测定蒙药肉蔻五味丸中的锗   总被引:1,自引:0,他引:1  
采用差分脉冲扫描法,在pH=1.30含有3,4-二羟基苯甲醛(DHB)的H2SO4底液中,测得无机锗的脉冲极谱波,峰电位为Ep=-0.53V,Ge()浓度在1.03×10-5—1.04×10-4mol·L-1范围内与峰电流呈线性关系,利用差分脉冲极谱法可以测定蒙药中总锗、无机锗和有机锗,得到了满意的结果。  相似文献   

3.
我们合成有机锗化合物的重要中间体 4-三氯锗基 - 4-甲基 - 2 -戊酮 ( A)、3-三氯锗基 -3,5,5-三甲基环己酮 ( B)、2 -三氯锗基 - 2 -苯基乙基苯基酮 ( C)、2 -三苯基锗基乙基苯基酮 ( D) ,测量了他们的 Raman和 IR光谱并进行了讨论。在化合物 A- D的 Raman和 IR光谱 ,苯环中的 C- H伸缩振动 ,饱和 C- H伸缩振动 ,饱和 Ge- C伸缩振动等特征数据基本一致。C=O伸缩振动在 Raman和 IR光谱中位置基本一致 ,但在红外光谱中均为强吸收带 ,而在 Raman光谱中的峰强度差别则非常大 ,化合物 A、D的峰非常弱 ,而 C的峰则很强 ,化合物 A- C的 Ge- Cl振动均在 390 cm- 1附近出现强峰。  相似文献   

4.
极谱分析法连续测定痕量铅和镉   总被引:13,自引:0,他引:13  
研究了 Pb2 + 和 Cd2 + 与 KCl-酒石酸钠 -三乙醇胺 -明胶体系的二次导数极谱波。在 p H=4 .5的 HAc-Na Ac介质中 ,Pb2 + 和 Cd2 + 分别于 - 0 .4 6 V和 - 0 .6 4V电位处产生一良好的极谱波。峰电流与 Pb2 + 和Cd2 + 的浓度分别在 1× 10 -5— 3× 10 -1g· L-1和 5× 10 -5— 6× 10 -3 g· L-1范围内呈线性关系。 Pb2 + 和Cd2 +的检出限分别为 1× 10 -7g·L-1和 5× 10 -7g·L-1。本法准确、简便、快速、选择性高。已直接用于饮料中铅和镉的连续测定 ,同时也对酒及面粉样品进行了测定 ,回收率分别为 99.9%— 10 0 .1%和 97.0 %—10 4 .8%。  相似文献   

5.
荧光素汞在碱性条件下具有很强的荧光,H2S能与荧光素汞结合,使其荧光猝灭,据此建立了一种荧光法测定大鼠肠灌流液中H2S含量的方法。在0.1mol·L-1 NaOH溶液中,以Na2S作为H2S供体,荧光素汞浓度为5.0×10-5 mol·L-1,Na2S浓度为1.0×10-5 mol·L-1时,以498nm为激发波长,在522nm处测定此二元体系的荧光强度。结果表明,在4.0×10-7~2.0×10-6 mol·L-1范围内,H2S浓度与荧光强度的下降程度呈良好的负相关性,r=0.998 0,精密度实验RSD=4.59%(n=7),检出限3.5×10-8 mol·L-1,样品中H2S含量分别为1.01×10-6和1.15×10-6 mol·L-1,加标回收率为95.8%~101.0%。该方法操作简单,灵敏度高,稳定性好,可准确测定肠灌流液中H2S含量,为内源性H2S的测定提供了依据。  相似文献   

6.
钨酸钇钠晶体中Tm3+的光谱特性   总被引:4,自引:2,他引:2       下载免费PDF全文
测量了Tm3 :NaY(WO4 ) 2 晶体的吸收光谱、发射光谱和激发光谱 ,利用J_O理论计算了钨酸钇钠晶体的强度参数 :Ω2 =7 2 130 4× 10 - 2 0 cm2 ,Ω4 =0 5 0 4 76 6× 10 - 2 0 cm2 ,Ω6 =0 977784× 10 - 2 0 cm2 ,以及Tm3 的光学参数包括各能级的荧光寿命和荧光分支比、积分发射截面等 ,在计算了Tm3 的自发辐射概率时 ,同时考虑了电偶极跃迁和磁偶极跃迁 .研究了其发光特性和跃迁通道 ,发现存在1 D2 3H6 →1 G4 3F4 的交叉弛豫  相似文献   

7.
GeO2含量对掺铒锗碲酸盐玻璃物性和光谱特性的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
本文研究了x GeO2-(70-x)TeO2-5K2O-5Na2O-10Nb2O5-10ZnO-0.2Er2O3(x=0,10,25,50,70(摩尔百分数))玻璃的物性和光谱特性,讨论GeO2含量对锗碲酸盐玻璃物性和光谱特性的影响.研究发现:GeO2的加入提高了碲酸盐玻璃热稳定性,并且使玻璃的最大声子能量略微增加;随GeO2的增加,掺Er3+锗碲酸盐玻璃的Judd-Ofelt强度参量Ω2和Ω6逐渐增大,但玻璃受激发射截面有减小的趋势;由McCumber理论,计算了掺铒锗碲酸盐玻璃在1.53μm处最大受激发射截面为9.92×10-21cm2,Er3+离子4I13//2→4I15/2发射谱的最大荧光半高宽为52nm,同时,实验发现,在977nm LD抽运下,掺铒锗碲酸盐玻璃存在较强的荧光上转换现象,随GeO2含量的增加,上转换荧光强度呈降低的趋势.  相似文献   

8.
利用激光泵浦一吸收技术,研究了在样品池中(T=385 K,H2气压400 Pa)的Rb(5DJ)+H2→RbH+H[x1∑+(υ"=0)]+H光化学反应过程.双光子激发Rb-H2混合蒸气中Rb原子至52D态,荧光中除有泵浦能级发生的直接荧光外,还包含由精细结构碰撞转移产生的敏化荧光,RbH分子是由5D原子与H2间的三体碰撞反应产生的.利用852 nm激光扫描RbH X1∑+(υ"=0→υ'=17)吸收带,△I'和△I"分别表示泵浦5D3/2和5D5/2时的吸收光强.泵浦室温下的纯Rb蒸气至5D3/2或5D5/2态,由于在低密度下52D精细结构混合可略去,故由5D3/2→5P1/2与5D5/2→5P3/2的荧光比得到泵浦率比.解速率方程组,得到5D3/2→5D5/2和5D→5D以外态的碰撞转移截面分别是9.8×10-16和2.0×10-16cm2,Rb(5DJ)+H2→RbH+H的反应截面分别是5.4×10-17(J=3/2)和2.3×10-17cm2(J=5/2),5D3/2与H2的反应活动性大于5D5/2,这与其他实验结果是一致的.  相似文献   

9.
林春 《光谱实验室》2004,21(6):1215-1217
在磷酸介质中 ,吐温 - 2 0存在下 ,锗 ( )与苯基荧光酮反应生成稳定的络合物 ,其最大吸收波长为5 0 0 nm,表观摩尔吸光系数ε=1.2 7× 10 5L· mol-1· cm-1。锗含量在 0— 10μg/2 5 m L范围内符合比耳定律 ,测得络合物的组成比为 :Ge( )∶苯基荧光酮 =1∶ 2。方法的灵敏度高 ,选择性好 ,络合物稳定 2 4 h以上 ,用于测定煤矸石中微量锗 ,结果令人满意  相似文献   

10.
应用Z扫描技术在甲苯溶液中研究了三种8辛烷氧基金属酞菁[(C8H17O)8PcZn(PcZn),(C8H17O)8PcNi(PcNi)和(C8H17O)8PcPb(PcPb)]在532nm对35ps脉冲激光的三阶非线性吸收和折射特性.用多能级模型拟合实验数据,得到三种酞菁的激发单重态吸收截面积σex分别为27×10-17cm2(PcZn),8.2×10-18cm2(PcNi)和3.4×10-18cm2(PcPb),相应的非线性折射率n2=-7.9×10-13,-5.5×10-13和-1.6×10-12esu,三种酞菁都具有自散焦效应.通过入射能流与透射能流的关系,研究了该类分子在甲苯溶液中在532nm对35ps脉冲激光的限幅特性,限幅机理是基于激发单重态的反饱和吸收.在TT0=0.5时,分别测定出它们的限幅阈值为60mJcm2(PcZn),80mJcm2(PcNi)和130mJcm2(PcPb).当入射能流达到500mJcm2时,相应的最高输出能流分别为40,80和150mJcm2,其中锌和镍酞菁的输出能流远低于同样条件下C60的输出能流(140mJcm2). 关键词: 光限幅 8-辛烷氧基金属酞菁 Z-扫描 非线性吸收  相似文献   

11.
锗是常用的红外光学材料。随着科学技术的不断发展,对锗零件的技术要求越来越高,其加工难度也越来越大。本文介绍一些加工锗双曲面的经验。  相似文献   

12.
TheK-Fluorescence Yield k of Germanium has been measured using the coincidence method and investigating the decay of74As. The branching ratios of this decay had to be measured and all relevant determining values, as detection efficiencies, absorption coefficients etc. The experimental results areP K K = 0.494±0.012 and K= 0.561±0.015 usingP K= 0.881±0.003. For the branching ratios of the decay of74As we obtainedEC 2 (1.204) 0.88±0.06%EC 1 (0.596) 32.8±0.8 % 1 + (0.596) 24.7±0.8 %EC 1 1 + =1.332±0.046.Additionally the half-lifeT 1/2=(17.76±0.03) d has been measured.  相似文献   

13.
In this Letter, the fabrication and characterization of a microsphere resonator from the semiconductor germanium is demonstrated. Whispering gallery modes are excited in a 46 μm diameter germanium microsphere resonator using evanescent coupling from a tapered silica optical fiber with a waist diameter of 2 μm. Resonances with Q factors as high as 3.8×10(4) at wavelengths near 2 μm are observed. Because of their ultrahigh optical nonlinearities and extremely broad transparency window, germanium microsphere resonators offer the potential for optical processing devices, in particular at long wavelengths, such as around 2 μm.  相似文献   

14.
15.
火焰原子吸收法测定有机锗(Ge.132)①中的锗,线性浓度范围为0-1.25mg/mL,方法精度为1.2%,相对标准偏差<2%,平均回收率为99.5%。杂质Pb和As用塞曼石墨炉原子吸收测定,Pb用(NH_4)_2HPO_4+Mg作改进剂,As用Pd作改进剂,特征质量分别为8.2pg和8pg,相对标准偏差分别为2.1%和2.2%,并讨论了有关机理问题。  相似文献   

16.
A dislocation structure is studied in germanium single crystals grown in a regime of minimum temperature gradients at the crystallization front and low supercooling. The investigations show that the distortion of the flat crystallization front arising during crystal droplet detachment in the completion growth stage results in the dislocation generation in the lower parts of dislocation-free single crystals. The dislocations are generated at the phase boundary and propagate in the thermoplasticity zone. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 21–24, May, 2005.  相似文献   

17.
随着红外技术的发展,在其光学系统中,锗材料的应用日趋地多。大口径锗材料在应力、均匀性和作为光学零件要求的精度上,对加工者都有一定难度。本文介绍了目前国内口径最大(Φ256mm)的多晶透镜的加工方法。从零件的特点及技术要求到加工工艺、磨具选择、抛光机理等均有叙述及分析。最后,提出进一步改进加工工艺的设想。  相似文献   

18.
In an effort to develop a material for infrared (IR) optics with improved parameters, bulk crystals of optical germanium doped with Na have been first grown and studied. Single-crystalline and coarse-crystalline Ge:Na boules of different shapes and dimensions, up to 10 kg by weight, have been grown. Sodium was incorporated into the Ge crystal during the crystal growing from the melt. Despite the fact that Na contamination in the source material was not strictly controlled, the density of Na in the grown crystals determined by the neutron activation analysis as well as by the glow discharge mass spectrometry did not exceed 1015 cm?3. Just this value may be supposed to be close to the solubility limit of Na incorporated in Ge in the course of bulk crystal growth. A first demonstration of donor behavior of Na in bulk Ge crystals is made by means of a thermoelectric type of testing. An interstitial location of Na impurity has been verified by experiments on donor drift in the dc electric field. The crystals are grown with free electron density in the range from 5?1013 to 4?1014 cm?3 which is optimal for using Ge crystals as an optical material for fabricating passive elements of the IR technique. A comparison between the properties of Ge:Na crystals and Ge crystals doped with Sb, a conventional impurity in optical germanium, grown under the same technological conditions and from the same intrinsic Ge as a source material, revealed a number of advantages of Ge:Na crystals; among them, the higher transparency in the IR region, smaller radiation scattering and higher regular optical transmission, lower dislocation density, more uniform distribution of electrical and optical characteristics over the crystal volume, the identity of optical parameters in the single-crystalline, and coarse-crystalline boules. No degradation of optical elements fabricated from Ge:Na crystals was detected in the course of their commercial application, starting from 1998.  相似文献   

19.
The electronic structure, lattice dynamics, and electron-phonon coupling of gallium-doped germanium are inves- tigated using ab initio supercell methods. Our results indicate the superconducting transition in gallium-doped germanium can be explained within a standard phonon mediated mechanism. The contribution of acoustic modes to the coupling constant A almost entirely comes from Ga related modes, and - 25% to λ. The calculated coupling constant is 0.35 and the corresponding transition temperature is 0.44 K for the gallium-doped germanium with 6.25% gallium content using Coulomb pseudopotential μ^* = 0.1, in agreement well with the experimental data.  相似文献   

20.
分光光度法测定饮料食品中痕量有机锗和无机锗的研究   总被引:6,自引:1,他引:5  
本文研究了在溴化十六烷基三甲基铵(CTMAB)抗坏血酸(Vc)存在下,苯基荧光酮(Pf)光度法测定痕量锗的最佳实验条件及配合物的组成,从而建立了测定痕是锗的新方法,其方法的灵敏度ε=1.034×10^5L.mol^-1.cm^-1锗含量在0-16.8μg/25mL范围内符合比耳定律,稳定性好,操作简便,快速。应用本法测定了矿泉水,茉莉花茶,大蒜中有机锗和无机锗的含量,回收率在91.6%-103.5  相似文献   

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